This invention relates to a medical instrument for the removal of plaque deposits from the walls of arteries and/or veins which is a vessel insertable, partially hollow and to an extent having a circular body in section, that is a practical, withdrawable and directable device, for the elimination of plaques by slicing off portions with cutting edges.
Arteriosclerosis, a chronic progressive, degenerative disease, especially located on the inner surface of artery walls (Intima), is an illness occurring very frequently in our civilized world, most commonly during the second half of normal life spans. For example, about 90% of such cases are the cause of arterial blockage diseases and holds the leading place in causes of death statistics. Through penetration of the thrombocytes in the cell interspaces, followed by lipoid containing deposits, the inner most walls of the vessels develop, what is known as atheromas changes, which leads to the death of cells and, finally, expanding of the connecting tissue at this artery wall site (Sclerosis). Through these changes the artery wall will lose its normal elasticity. Focal deposits, especially Cholesterin crystals that also penetrate to the middle of the vessel wall, lead to inflammatory reaction and more cell deaths. This results in calcium deposits, which cause growths in the vessel lumen, later attracting thrombosis.
There are cases wherein arteriosclerosis can be treated with medicines, dilating the vessel to increase the flow of blood. There exist some physio-therapeutic facilities that lead to improved circulation, in addition to which, some surgical procedures have been developed to treat arteriosclerosis. The surgical treatment of arteriosclerosis changes when particular organs or parts of the body are utilized. Vascular surgery can be successfully applied, especially in the following cases:
a) Arteriosclerosis alteration to the carotid artery that supplies blood to the brain.
b) Arteriosclerosis alteration to the coronary arteries: Coronary bypass and implanting, Arteria Thoracica Interna.
c) Serious arteriosclerosis disturbs the supply of blood to the extremities.
d) Arteriosclerosis to the kidney arteries.
e) The removal of Aneurysms.
Generally, with arteriosclerosis change, the following surgical techniques are applied:
a) The method of bypass, during which the closed artery is replaced by a section of the patient's vein or artery, or, synthetic material in the format of a vessel, to bridge the flow of blood into certain areas.
b) Edarteriaoectomy.
c) Implanting of a patch after endarteriaoectomy.
d) Implanting of a vessel prothesis, either as a replacement or bypass for the arteriosclerosis artery.
e) Sympathectomy.
f) Removing arteriosclerosis changes by the means of a balloon catheter.
As is known, arteriosclerosis changes are located mainly on internal walls of arteries, while the external walls remain relatively normal. When inner sclerotic material is removed or sliced from the internal wall, the surface is left smooth. For example, this can be performed with an instrument, such as is described in U.S. Pat. No. 4,765,332. This acknowledged instrument contains a somewhat basic cylindrical format with a pull-back cutting section that is also of cylindrical shape. The sharp edges of the cutting section are directed from the inside to the outside of the body which could lead to the injury of healthy vessels.